The invention relates generally to semiconductor integrated circuits, and more particularly, to an apparatus and method for forming circuits with one or more inductors and a spherical-shaped semiconductor substrate.
Electrical devices such as semiconductor integrated circuits are advancing in many ways. For example, many devices are seeing an increase in overall size, and number of components and transistors. Furthermore, devices are encompassing more and more peripheral components on a circuit board. As a result, space is saved and communication speed is increased.
However, these semiconductor integrated circuits have not been able to encompass many different circuits. For example, circuits that utilize a conductor coil or an inductor have not been successfully implemented on a semiconductor integrated circuit. This is due, in part, to the relatively flat nature of conventional integrated circuits.
Conventional integrated circuit devices, or "chips," are formed from a flat surface semiconductor wafer. The semiconductor wafer is first manufactured in a semiconductor material manufacturing facility and is then provided to a fabrication facility. At the latter facility, several layers are processed onto the semiconductor wafer surface. Once completed, the wafer is then cut into one or more chips and assembled into packages. Although the processed chip includes several layers fabricated thereon, the chip still remains relatively flat. As a result, forming an inductor on a chip is difficult, if not impossible.
Referring to FIG. 1, one typical peripheral component for many circuit boards is a power circuit 10, represented here with a single phase rectifier. The power circuit 10 receives alternating current ("AC") power from a source 12 and reduces the voltage level of the source 12 with a transformer 14. The transformer 14 includes a primary coil 16 and a secondary coil 18. The secondary coil 18 is further connected to a bridge circuit 20, which provides a rectified, direct current ("DC") voltage to a load 22. Power circuits have not been incorporated onto conventional semiconductor devices.
Referring to FIGS. 2a and 2b, another typical peripheral component for many circuit boards is an antenna for transmitting or receiving electromagnetic waves. Two examples of an antenna include a loop antenna 24 (FIG. 2a) and a helical antenna 26 (FIG. 2b). Antennas have also not been incorporated onto conventional semiconductor devices.
In parent application Ser. No. 08/858,004 filed on May 16, 1997, a method and apparatus for manufacturing spherical-shaped semiconductor integrated circuit devices is disclosed. The present invention provides an apparatus and method for forming an inductor on the spherical shaped integrated circuit. The inductor may be used in a rectifier circuit and/or an antenna. Further, the antenna can be used to support communications from the integrated circuit device with other components.